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The dam debate yet again by Aamir Kabir , The Dawn, Pakistan - 25 December 2000 With the release of a report, Dams and Development, by the World Commission on Dams (WCD) recently, a debate on large dams has begun once again all around the world.The report and the commission have a close association with Pakistan because Tarbela dam was one of the ten announced case studies under taken by WCD during its two year work program. As expected, the commission discourages large dams and supports small dams and reservoirs. Since the establishment of the commission in February 1998, it was believed that it was going to rule out large water reservoir construction all around the world. The mandate of the commission was to review the development effectiveness of dams and to develop standards, criteria and guidelines to advise future decision-makers. As reported in the press, the commission has also sought comments from all the four provinces of Pakistan on this report and it seems that we are at the cross road right now to decide that should we go with or against the commission's recommendations? The most severe water shortage of history is forcing us to go for the large dams and on the other hand international donor agencies, like the World Bank, on whose behest the commission was set up, are compelling us otherwise. It will be worthwhile to note that there are more than 800,000 dams in the world today, out of which 47450 are classed as large dams by the definition of International Commission on Large Dams (ICOLD) which defines large dams as dams which have a height of 15 meters or more. If dams between 10-15 meter high have a spillway discharge of over 2000 cubic meter or a reservoir volume of more than one million cubic meters, they are also classified as large dams. However International Journal on Hydropower & Dams uses the term "major dam project" for dams that fulfil one or more of the following criteria: dam height of more than 15 meters, dam volume of more than 15 million cubic meters; reservoir volume of more than 25 billion cubic meters; and installed capacity of more than 1000 MW. There are more than 300 dams of this category worldwide. Interestingly Pakistan, despite of having world's largest contiguous irrigation system, stands no where in the statistics of large dams worldwide and has only 40 dams that qualify the definition of ICOLD. Whereas according to definition of the Journal of Hydropower and Dams, we have only two large dams i.e. Tarbela and Mangla. Therefore we need not to take care about rulings of such commissions which have their own interests that do not match our requirements any way. Worldwide statistics of large dams are being presented in the table. Country No. of dams China 22000 USA 6575 India 4291 Japan 2675 Spain 1196 Canada 783 S. Korea 765 Turkey 625 Brazil 594 France 569 Other countries 7347 For an agricultural country like ours water is not the only limiting factor in our agriculture-cum-economic development. With each passing day we are turning to be an energy deficient country as well and in the years to come, water shortages will not be the only issue for our development but more appropriately, subsistence. In the coming future, it will be the energy issue that will dictate its terms. Broadly speaking there are two main issues confronting our rural and urban life now a days. Rural people are crying for water shortages whereas urban people for regular power breakdown and inflated electricity cost. In these circumstances, we need to evolve a strategy that will relieve our rural areas, or in other words agriculture, from frequent water shortages and our urban areas, or in other words industry, from regular power failure and its inflated cost. There is no option other than the hydropower, which suits us best in this current scenario. Before debating the issue of large dam construction, we ought to distinguish between water development and water management. Majority of developed countries of the world have surpassed the water development course and are now focusing their attention on water management and conservation. That is why they have turned opponents of water development projects, or in other words large dams, in developing countries like ours. Water resources policy of almost all developed countries was defined in the past by the flow of money to dams and canals. The era, however, is ending for three reasons: (1) federal support has dwindled; (2) general public has shown a strong interest in preserving its rivers for recreation and wildlife; and (3) many best sites for dams have been used and those that remain will be more expensive to develop and are often more environmentally objectionable. Therefore their water policy has shifted from water development to the efficient use of existing facilities and supplies, making water conservation and recycling wave of future. On the other hand, Pakistan has not been able as yet to develop its water resources properly. Designed storage capacity of three storage reservoirs (Mangla, Tarbela and Chasma) is 15.7 MAF, that at present has reduced to 12.5 MAF (approximately) due to siltation. One thing must be borne in mind that reservoir siltation is a natural process which can never be eliminated completely. However, it may be reduced by proper basin management. No cost-effective widely applicable way to un-silt a large reservoir has yet been developed, so useful life of all dams is reduced due to this natural phenomenon. We are fortunate enough that our water reservoirs are not being silted up swiftly as compared to a number of reservoirs in other countries. It has been estimated that about 15 per cent of the world's river flow is now channelled into reservoirs and that in Europe and North America over 40 per cent of stable discharge is regulated by dams. In contrast, Pakistan has been able to channel less than 10 per cent of its water to regulate water reservoirs. Based on 50 year rim-stations inflow data, it is estimated that Pakistan has a mean annual surface water availability of about 141 MAF. Of this mean annual availability of water, only 23.04 MAF (16.3 per cent) is available during the six Rabi months (October-March), 44.45 MAF (31.3 per cent) during the first three months of Kharif (April-June) and 73.36 MAF (52.1 per cent) during last three Kharif months (July-September). Interestingly about 42 per cent of the total annual mean flow is available during the two months of July and August. Our river flows are almost fully utilized, except during the flood period in Kharif. The utility of flood water is very marginal unless additional storage is provided in the system to broaden the supply period. According to a World Bank report, Pakistan does not have enough reservoir capacity in its irrigation system to store seasonal waters. Additional storage would also be necessary for providing the flexibility needed by the shift from a supply-based operation system towards a demand-based one. Irrigation, drainage and flood control of agricultural lands are no longer options. They are a necessity for feeding millions of people and providing employment for millions of the rural poor. Large dams provide large storage capacity to meet the need during the dry period, thus following for reliable delivery of water to the crops when most needed. There is a close link between water availability and agricultural productivity. It is a dire need of Pakistan to ensure its food security for its rapidly expanding population. The obvious question, therefore, is as to where from would come additional water needed for sustained agricultural production. Water conservation measures and small scale irrigation projects combined with efficient use of water can help water shortages to a small extent but not eliminate the necessity of large multipurpose dams as is being projected by opponents of large dams. The basic strategy for a sustained agricultural production increase is to bring additional land under cultivation through intensive/extensive irrigation practices. For this purpose, the only exploitable water resource available to our country is the surplus flood flow of rivers which goes unused to sea during the two months of July and August. Storage of this water not only can bring vast barren lands under plough but could produce substantial electricity as well at a far cheaper rate then being bought from the Independent Power Producers (IPPs). For an arid country like ours, irrigation can mean the realization of otherwise unimaginable opportunities. Statistics of canal head diversion reveal that water resources increased from 67 MAF in 1949-50 to 95 MAF in 1967-68 after the commissioning of Mangla Dam. It reached its peak at 112 MAF during post-Tarbela period (1977-92). Since then, canal head diversions are stagnating rather reducing, due to absence of new storage provision and gradual silting problems. In this critical scenario of the worst water shortages of our history we do not have any option other than to build new multi purpose water reservoirs, whatsoever or wheresoever it may be. The question before us is not to debate that should we construct new dams or not but is how to seek agreement between upper and lower riparian for settling the water rights issue among them
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